Multiple flanged fin for heat exchangers and method of producting individual fins



Fb. 23, 1954 B. sPlETH 2,669,959

MULTIPLE F'LANGED FIN FOR HEAT EXCHANGERS AND METHOD OF PRODUCING INDIVIDUAL FINS Filed oct. 24, 1947 Patented Feb. 23, 1954 GHANGERS ANB. METIiQl-QF BRQDUQ-A' ING INDIYIDHAL FINS BenjaminfSpieth, Racine, Wis., assgnorto Medine lvianutacturing= Gompany; Racine, Wis., a corporation ofiwisconsin Application Qctnber, 24, 1%47. Serial Na 7.8.1.,2i2it4 Slaimsl 1.

This inventionl relates to multiple length nn for heat exchangers and the method off making fins,I and its principal object is to permit of quantity production of units andv of assemblies, with a considerable saving of time. The heat exchange element of many types of apparatus; forex-ample,v a convector as used for herne heating, requires a considerable number of relatiyely short ns. These fins are ordinarily in the range of 3 1/2 inches toy 10 inches long. In modern shop practice, only one iin would be made at each stroke of a press. Such an operationinA itself is relatively slow andhence, costly. Eurthermore, it is probable that these individual iins must be handled singly in subsequent assem- -1 bly operations, and such an operation is, costly where thousands of parts areY to be assembled,

I' propose to make a multiple, length n, each multiple length, say 26* inches to 36 inches long. Each multiple length 1in is, produced at each stroke of a punch press. Thus, there is a oonsiderable saving in strokes, with resultantsaving in time, when producing a givenv number of completer units. Likewise,l experience shows that multiple length fins can be assembled with tubes consuming but little more time than a single length fin.

To accomplish the desired objects, Il' have de,- s-igned a multiple length nn which may be readily formed, be readily handled and assembled into multiple assemblies, the multiple assemblies processed as a unil?, and a feature ofI the design wherein the multiple assembly can be readily and accurately parted into the iinal units of desired width.. Provisions are incorporated in the design so that after the multipleassembly has been parted into unit assemblies, there are pro visions for readily attaching side plates, or side guards. The details of this means for attachment. andthe design of the sideplates `inthe, subject of my copending application, Serial No. 7176,- 363, led September 26, 1941, for'v patent onlieating Element for Convection Heaters, now- Patent No. 2,545,561, issued March 2,0, 1951.

With these and other objects and advantages in view, this invention consists in the Several novel features of construction herein described, and in the herein described method of making fins as more particularly dened in the. appended claims.

The invention is clearly .illustrated in the accompanying drawing, in which:

Fig. 1 is a side elevation partly broken away of a multiple length nn embodying a simple form of the present invention;

Fie. 2 is a detail` vertical section taken on the line 2*-2 Qi Eig... A1.;

Fia 3 is .a fragmental detail. horizontal section tak-.en on the line 3.-.3. ,ci Fia.. 1;.

Fig. 4 is a perspective view of a fragment of one of the individual ins;

Fie.. 5. is. a View uariliilin verticali Cross., Secticn ,and partir in elevation. 0f. a Side aleta and. fre-e.-

nient of a cfa beat exchanger coreani 6' isa detail horizontal' Section taken 0.11 the. line 6--6 oiFia.

Referring to saidldrawing, the reference character Il! designates a multiple length` rin from which a number of individual fins are to be parted.

The multiple length fin isv given its shape with suitable dies in a punch press, at one operation. Fla-ngedholes IIY, i2 are struck up with suitable dies at suitable spaces. individual nhs, made from multiple length fins, may havetwo or more h oles as the case may be, and the drawing the sections, which comprisethe individual fins each have three holes H or I2 .as illustrated'.

At the ends of each section which denethe ends of the individual fins, the metalis slit at the edge portions and intermediate the edge p ortions and striickv upV to form flanges i3, I4 arranged n aligned pairs with a blank space between the flanges of each pair. Between the 'pairs offlan-ges, the metal isst-ruck up with sui-table dies to provide aligned beads f5 preferably of concavo-convex form with their ,crowns disposed midway between the planes of the @anges of each pair.

For stiffening the individual ns, concaveconvex beads H5, I6, that run lengthwise ofi-the multiple length n adjacent the edges thereof are strucky up with suitable dies.

The punch press upon which the multiple length nn is. plan-hed up` may have retractible nuncheswhich strike up the anges i3, lili1 and beads t5, and only those punches which are to be used: in striking up. said flanges and beads at the ends of sections which comprise the individual nus are set into. yoperati-ve position. Those anges i3, I4. and beads l5 which are-illustrated in solid lines in` Fig. 1 indicatev the anges and beads of each individual fin section, wherein three holes Isl" areprovidedin each 'individual fin. If the individual iins areto contain two holes `I l', the punches are set -to strike up the lian-ges and beads indicated at a, b; if the individual fins are to contain fourholes, the punches are set to strike up. the dangers and; beads indicated at b, and after each subsequent group of four holes,

.and inthe individual-nus are @contain fiveA holes,

,have been im.; :the 4rrniltirile are as- @o .semblait en to tubes, usually several ens persinch as conditions demand, by any suitable means and quire that the fin stock have a coating of solder before the ns are formed in dies.

When the multiple slab hasA been completed as far as possible, it may be divided into units by a band saw. Experience proves that aband -saw directed into the bottom' of the formed beads will be constrained to remain in the bottom ofV the bead, until the fin is parted. This action continues as the saw blade severs the individual fins in quick succession through the length of the slab assembly. quickly, economically and accurately separating the slab assembly into individual units.

The sawing of the slab is repeated at each division point and the end pieces I6 are sawed oil and become waste. Thus, each multiple length iin is divided into a plurality of individual fins indicated by la in Figs. 4, 5 and 6.

In making up individual cores, side plates I1 A(see Figs. 5 and 6) are soldered or brazed Yto the in its proper position during the sawing operation.

Having thus described my invention, it is obvious that various immaterial modifications may be made in the same without departing from the spirit of my invention; hence, I do not wish to be understood as limiting myself to the exact form, construction, arrangement and combination of parts herein shown and described or uses mentioned.

What I claim as new and desire to secure by Letters Patent is: I

1. In a multiple length ilanged iin forheat exchangers, the combination of an elongated metal 1in strip having a plurality of longitudinally spaced rows of openings therein, each row extending transversely across the strip, the openings of each row being transversely spaced and defining the juncture of adjacent individual n seci tions, with the material between the respective openings of each row forming a plurality of con necting strips between adjacent n sections operative to retain the latter in a single multiple strip, the connecting strips of each row being formed in the shape of concavo-convex beads and adapted to be severed thereat to form individual iin sections, the beads of each respective row being aligned, the corresponding face of each n section having iianges extending outwardly therefrom and transversely to the plane of such iin section, said flanges forming the transverse edges of the respective openings and being formed from metal originally occupying the area of the respective openings therebetween, said edges extending parallel to one another, and each fin section having one or more tube receiving holes therein.

2. In a multiple length ilanged n for heat exchangers, the combination of an elongated metal n strip having a plurality of longitudinalv1y spaced rows of elongated openings therein,

4 ,s the openings of each row being transversely spaced with the long axis 0f such openings being in alignment and defining the juncture of adjacent individual 1in sections, with the material between the adjacent ends of the respective openings of each row forming a plurality of connecting strips between adjacent iin sections operative to retain the latter in a single multiple strip, each iin section having iianges extending transversely to the plane thereof and forming the transverse edges of the respective openings, with the flanges on adjacent iin sections lying in parallel planes,

. said flanges being formed from portions of the Thus, the design provides means for The flanges, although primarily metal originally occupying the area of the opening therebetween, said connecting strips being deformed out of the plane of said n sections to provide a concavo-convex bead adapted to guide a severing tool between said anges, and each fin section having one or more tube receivingv holes therein.

3. The method of producing individual flanged iin sections, which comprises the steps: forming tube receiving holes in a rectangular multiple length fin strip, severing longitudinally adjacent portions of said strip and bending the same outwardly from the plane of said strip to form a plurality of longitudinally spaced rows of aligned transversely spaced openings in said sheet, adjacent rows of openings dening the length of individual n sections, with the longitudinally opposite edges of each opening being defined by oppositely disposed rectangular anges formed from portions of the material originally occupyying the area of the opening therebetween and lying in planes extending substantially perpendicularly to the plane of said strip with said fin sections connected to -one another at a plurality vof points by the remaining material extending References cited in the nie of this patent UNITED STATES PATENTS Number Name Date 517,580 Livingston Apr. 3, 1894 950,524 Whytock Mar. 1, 1910 1,282,567 Goetz Oct. 22, 1918 1,599,792 Sage Sept. 14, 1926 1,691,491 Nelson Nov. 13, 1928 1,693,045 Murray Nov. 27, 1928 1,767,605 Modine June 24, 1930 1,886,066 Stuart Nov. 1, 1932 1,976,929 Elliott Oct. 16, 1934 2,046,791 Przyborowski July 7, 1936 2,168,549 Young Aug. 8, 1939 2,204,332 Trent June 11, 1940 2,211,813 Franco-Ferreira Aug. 20,1940

l2,246,258 Lehman June 17, 1 941 2,500,384 Schell Mar. 14, 1950 FOREIGN PATENTS Number Country Date 23,482 Great Britain of 1905 579,563 France of 1924 4667,479 France Oct. 17,1929 843,160 France June 27, 1939 

